repeat
Yields the same value n times — a lazy, finite source for padding and pairing.
Lecture
repeat(n, value) yields value exactly
n times, then stops — it's finite and lazy, like the rest
of this section's generators. Note that it repeats the same
value (or the same object reference, for non-primitives) every time; if
you need a fresh value per iteration, generate it separately (e.g. with
map over the result) rather than expecting
repeat to call a factory function.
It's most useful paired with something else: zip it
against a variable-length sequence to stamp a constant label onto every
element, or use fx(...).join() to build a fixed-width
separator string. repeat(0, value) is a valid, perfectly
normal way to get an empty iterable.
If you actually want to repeat a whole sequence rather than
one value — and keep going forever instead of a fixed n
times — that's cycle, covered next.
Demo 1 · Basics
Demo 2 · Pairing a constant with a variable sequence
repeat yields the SAME value every time — pair it with
zip to stamp a constant onto a variable-length sequence:
Try it yourself
Exercise: build a 5-item List<int> of the value 7
using repeat.